# -*- codeing = utf-8 -*-

class Pagination(object):
    def __init__(self,current_page,all_count,base_url,query_params,per_page=30,pager_page_count=11):
        """
        分页初始化
        :param current_page:
        :param all_count:
        :param base_url:
        :param query_params:
        :param per_page:
        :param pager_page_count:
        """
        self.base_url = base_url
        try:
            self.current_page = int(current_page)
            if self.current_page <= 0:
                self.current_page = 1
        except Exception as e:
            self.current_page = 1
        query_params = query_params.copy()
        query_params._mutable = True
        self.query_params = query_params
        self.per_page = per_page
        self.all_count = all_count
        self.pager_page_count = pager_page_count
        pager_count, b = divmod(all_count,per_page)
        if b != 0:
            pager_count += 1
        self.pager_count = pager_count

        half_pager_page_count = int(pager_page_count / 2)
        self.half_pager_page_count = half_pager_page_count

    @property
    def start(self):
        """
        数据获取值起始索引
        :return:
        """
        return (self.current_page - 1) * self.per_page

    @property
    def end(self):
        """
        数据获取值结束索引
        :return:
        """
        return self.current_page * self.per_page

    def page_html(self):
        """
        生成html页面
        :return:
        """
        if self.all_count == 0:
            return ""

        #如果数据总页面pager_count<11 pager_page_count
        if self.pager_count < self.pager_page_count:
            pager_start = 1
            pager_end = self.pager_count
        else:
            #数据页面已经超过11
            #判断： 如果当前页 <= 5 half_pager_page_count
            if self.current_page <= self.half_pager_page_count:
                pager_start = 1
                pager_end = self.pager_page_count
            else:
                # 如果： 当前页+5 > 总页码
                if (self.current_page + self.half_pager_page_count) > self.pager_count:
                    pager_end = self.pager_count
                    pager_start  = self.pager_count - self.pager_page_count + 1
                else:
                    pager_start = self.current_page - self.half_pager_page_count
                    pager_end = self.current_page + self.half_pager_page_count

        page_list = []

        if self.current_page <=1:
            prev = '<li><a href="#">上一页</a></li>'
        else:
            self.query_params['page'] = self.current_page -1
            prev = '<li><a href="%s?%s">上一页</a></li>' % (self.base_url,self.query_params.urlencode())
        page_list.append(prev)
        for i in range(pager_start,pager_end+1):
            self.query_params['page'] = i
            if self.current_page == i:
                tpl = '<li class="active"><a href="%s?%s">%s</a></li>'% (self.base_url,self.query_params.urlencode(),i,)
            else:
                tpl = '<li><a href="%s?%s">%s</a></li>'% (self.base_url,self.query_params.urlencode(),i,)
            page_list.append(tpl)

        if self.current_page >= self.pager_count:
            nex = '<li><a href="#">下一页</a></li>'
        else:
            self.query_params['page'] = self.current_page + 1
            nex = '<li><a href="%s?%s">下一页</a></li>'% (self.base_url,self.query_params.urlencode(),)
        page_list.append(nex)

        if self.all_count:
            tpl = '<li class="disabled"><a>共%s条数据，页码%s/%s页</a></li>'% (self.all_count,self.current_page,self.pager_count,)
            page_list.append(tpl)
        page_str = ''.join(page_list)
        return page_str












